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Answers To The Top 3 Questions About Crawl Space Humidity

By Mike on September 23, 2016

Crawl spaces are tricky to monitor and maintain, and homeowners need to know where to start. We spend a lot of time talking about the dangers of moisture in your crawl space, but what should your next step be? The main concerns homeowners have are about mold growth, condensation and the dangerous levels of crawl space humidity. The answers to these top three questions give practical recommendations to maintaining your crawl space in good shape and avoiding moisture damage and mold.

Crawl Space Humidity

“What’s the threshold humidity level for mold growth?”

When the relative humidity of your crawl space is 70% or higher, mold can thrive. “Relative” humidity is the humidity level expressed in a percentage of the amount of moisture in the air needed for “saturation” (i.e. the highest level of humidity – 100%). The amount of water the air can hold (humidity level) depends on the temperature of the air itself. Colder temperatures hold less moisture. Homeowners should be wary of the condition of their crawl space when the humidity level begins to creep up past 70% relative humidity. If that is the case, then mold is on its way.

“I’m seeing condensation. What does that mean?”

Condensation is an indication that the air within your crawl space has reached 100% relative humidity. The air can no longer hold the moisture and it’s condensing on the surfaces in the vicinity. This causes the organic materials that make up your crawl space to become damp, inviting toxic mold to set up shop. When mold and mildew begin to grow, the air quality in your home decreases significantly. Individuals who struggle with asthma or other respiratory issues will be the first to feel the effects, and other health risks may follow if the mold is allowed to spread.

“How do I know when the humidity in my crawl space is at a dangerous level?”

A hygrometer is a device used to measure the humidity of indoor air. Using this tool to measure the humidity of your crawl space is a great way to monitor the amount of moisture present. These devices can be purchased at a small cost— as little as ten bucks. Rest assured that everything is hunky-dory when the humidity level is below 70%. However, as soon as it approaches 70%, it’s time to break out the dehumidifier.

A thermo-hygrometer measures both temperature and humidity level. These devices are even better for crawl space atmosphere monitoring because the relative humidity level is contingent to the moisture in the air, in relation to the air’s temperature. Being able to track the changes in both of these conditions in your crawl space will allow you to see trends and anticipate necessary changes.

For instance, if the weather is hot during the day but the temperature plummets at night, the change in temperature can cause problems for your crawl space’s humidity levels. The daytime temperature is higher, which allows the air to hold more moisture. As night approaches and the air cools, the amount of moisture the air can hold also decreases – causing the relative humidity level to rise. A crawl space that was at a permissible humidity level during the day can run into problems when night falls. Being able to see these changes on your thermo-hygrometer can help you identify these types of trends so that you can respond appropriately.

Keep in mind that properly insulating your crawl space and installing vapor barriers will help regulate the temperature and keep moisture levels down, resulting in fewer fluctuations in the air’s relative humidity. This will prevent mold, mildew, and rot in both the short-term and in the long run.

Crawl Space Humidity insulation

Your Next Step Should Be…

We would suggest that you purchase a hygrometer or a thermo-hygrometer to ensure that your crawl space’s humidity is at a safe level. If your crawl space is already obviously damp, is lacking an adequate vapor barrier, or is poorly insulated, it would be wise to address those issues as soon as possible.

Insulation, in particular, can make or break the moisture levels in your home. If your crawl space insulation is too old or damaged, it will not perform at the desired level, allowing unwanted air transfer and moisture. If your crawl space is inadequately or improperly insulated, the same problem will occur, this time under the impression that everything is fine.

At Clean Crawls, our team of professionals can inspect your crawl space, attic, and other areas of the home and determine whether you need new insulation. The last thing you want is to overwork your HVAC system and deal with excess moisture and humidity. At Clean Crawls, we can help you prevent that. In fact, you can save greatly on your monthly energy bills by hiring our professional crew to replace your ineffective insulation.

As mentioned above, vapor barriers also contribute to the war against moisture in your crawl space. By keeping moisture from entering your crawl space, vapor barriers protect the structure and subfloor of your home from the ravaging of mold, mildew, and rot. Vapor barriers also prevent nasty odors, allergy triggers, and stop animals like insects and rodents from invading your home. Pest invasions can be especially damaging, so investing in an effective vapor barrier to prevent major animals is well-worth it.

Should you choose to contact the Clean Crawls team for an insulation inspection, don’t forget to ask about vapor barrier options and replacement. Our qualified professionals are experts in both insulation and vapor barrier installation, and they know exactly what each home needs to eliminate the risk of damaging humidity in the crawl space.

Contact Crawl Space Professionals

For information about crawl space cleanout, insulation, or vapor barriers, contact Clean Crawls. We’ve been thrilled to work with an array of Northwest homeowners to provide them with a clean crawl space and healthy air quality. We hope that we can serve you in the same way, creating a safer, more comfortable living space for you and your family.

Call our team today at 866.610.3556 or get a free quote by filling out our contact form.

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